Finding the Fourth Proportional to 1,428.12, 1,970.22 and 930.58

Step by Step Solution

1. Step 1: Write the proportion equation
   1,428.12 : 1,970.22 = 930.58 : x
2. Step 2: Convert to fraction form
   1,428.12/1,970.22 = 930.58/x
3. Step 3: Cross multiply
   1,428.12x = 1,970.22 × 930.58
4. Step 4: Simplify right side
   1,428.12x = 1,833,447.33
5. Step 5: Solve for x
   x = 1,833,447.33/1,428.12
6. Step 6: Final answer
   x = 1,283.82